Schneider ACE850FO Communication Interface Module

(Part No.: 59659)

The ACE850FO is a fiber-optic multi-protocol communication interface module dedicated to Sepam series protective relays. It is compatible with Sepam 40/60/80 series protection IEDs, equipped with dual 100BASE-FX fiber Ethernet ports for substation bay-level networking. It supports RSTP ring topology and is suitable for switchgear cabinets with severe electromagnetic interference.

Comparison within the same series: ACE850TP is the RJ45 copper version; ACE850FO is the fiber SC version.

Status: Marked End-of-Life (EOL). Last order date: 2026-12-31; support & maintenance until 2030-12-31.

Model Definition

ACE850: Sepam communication interface family

FO = Fiber Optic, fiber optic variant

Material / Part Number: 59659

Core Technical Specifications

1. Fiber Port Specifications

Speed: 100BASE-FX

Fiber type: Multi-mode fiber

Wavelength: 1300 nm

Connector: SC

Dual fiber ports: S-LAN (Supervision Network) and E-LAN (Engineering Network); ring topology supported

2. Supported Protocol Stack

IEC 61850 MMS / GOOSE

Modbus TCP

RSTP (IEEE802.1d 2004 Rapid Spanning Tree, ring redundancy)

SNMP, FTP, HTTP, SNTP, ARP

3. Compatible Host IEDs: Sepam 40 / Sepam 60 / Sepam 80 (including Sepam80 NPP)
4. Power Supply: Powered from the Sepam unit itself; no separate power required
5. Default Login Credentials

User: Admin

Password: ACE850

Port Definition

S-LAN: Supervision network, connects to SCADA backend, carries IEC61850 and Modbus TCP traffic

E-LAN: Engineering maintenance port, used for SFT2841 software local/remote commissioning and parameter download

Both ports share identical hardware; functions are differentiated by software. Star and fiber ring network topologies are supported.

Typical Application Scenarios

Fiber networking of Sepam protection relays in medium-voltage switchgear for EMI immunity

IEC61850 digital protection at substation bay level

Dual-network redundancy and fast self-healing fiber ring for IEDs

Migration & Replacement Guidelines

ACE850FO is discontinued. New projects are not recommended for procurement; spare parts are limited to existing stock. New design options:

1. Upgrade to new-generation Sepam protection relays with built-in IEC61850 fiber ports, eliminating external ACE850 modules
2. Retrofit for existing Sepam40/80: evaluate full IED replacement or third-party optical-electrical converters (GOOSE latency must be validated)

Troubleshooting Checklist

1. Optical link: Inspect SC connector endface cleanliness, verify multi-mode fiber matching and optical power. 100BASE-FX does not work with single-mode fiber.
2. Ring network: RSTP configuration. Avoid multiple root bridges within one ring; guard against GOOSE storm.
3. Communication: Distinguish S-LAN and E-LAN. E-LAN is for SFT2841 commissioning only; do not permanently connect to SCADA supervision network.
4. Login: Password reset requires factory reset, which erases all network configuration.

Supporting Software

SFT2841: Configuration and commissioning software for Sepam protection relays. Connect to the E-LAN port of ACE850 for parameter download and oscillography retrieval.

Full Model List for Schneider Sepam 40 / 60 / 80 Series Protection IEDs (Compatible with ACE850FO)

Prefix definition:

S: Feeder / incoming line protection

T: Transformer protection

M: Motor protection

G: Generator protection

B: Busbar protection

C: Capacitor protection

All models use the same hardware platform; protection functions are determined by embedded application firmware. Communication extension via ACE850TP (copper) / ACE850FO (fiber SC). Whole series EOL discontinued.

Sepam 40 Series (Economical, basic distribution protection, 13 models)

S40: Feeder protection (basic overcurrent & earth fault)

S41: Directional feeder protection

S42: Dual-source / busbar ATS, parallel incoming line protection

S50: Voltage protection (PT cabinet, busbar voltage monitoring)

S51: Voltage + overcurrent protection

S52: Incoming + busbar, automatic transfer

S53: Directional residual earth fault protection

S54: Sensitive earth fault protection

T40: Distribution transformer protection (medium & small transformers)

T42: Transformer + automatic transfer

T50: Transformer voltage monitoring protection

T52: Transformer + incoming interlock

M41: Medium-voltage motor protection

G40: Small generator protection

Positioning: Basic medium-voltage switchgear, limited I/O, low sampling rate for fault recording, suitable for simple distribution networks.

Sepam 60 Series (Enhanced, complex distribution applications, 8 models)

S60: Feeder protection

S62: Parallel incoming line / busbar ATS

M61: Medium-voltage motor protection (heavy-duty motors)

T60: Transformer protection

T62: Transformer + incoming interlock

G60: Generator protection

G62: Generator paralleling protection

C60: Capacitor bank protection

Positioning: More I/O and stronger logic than Sepam40; supports advanced custom logic. Three HMI panel options available.

Sepam 80 Series (High-end, programmable, 16 models, most commonly paired with ACE850FO)

S80: Basic feeder protection

S81: Directional overcurrent feeder protection

S82: Parallel incoming line / busbar ATS

S84: Incoming protection with directional residual and islanding detection

T81: Transformer protection

T82: Transformer + automatic transfer

T87: Main transformer protection with Buchholz and temperature monitoring

M81: Medium-voltage motor protection

M87: High-power motor with temperature and bearing monitoring

M88: Motor-transformer unit protection

G82: Generator protection

G87: Full generator protection (loss of excitation, reverse power, etc.)

G88: Generator paralleling protection

B80: Basic busbar protection

B83: Busbar differential protection

C86: Capacitor bank protection (multi-section capacitor, unbalance protection)

Positioning: Top-tier Sepam family. Supports Logipam custom programmable logic, 36 samples per cycle fault recording, abundant I/O resources. Widely used in digital substations for GOOSE over ACE850FO.

Cross-Series Comparison for Selection

Supplementary Information

1. Unified commissioning software: SFT2841. Connect PC to ACE850FO E-LAN for parameter download and fault record retrieval.
2. Hardware: Native RS485 on IED; IEC61850 / GOOSE over fiber requires external ACE850FO (59659).
3. EOL Status: Sepam 40/60/80 IEDs and ACE850FO are discontinued. New projects recommended to adopt Easergy P3 / P5 series.

Application Scenarios of Sepam 40 / 60 / 80 Protection IEDs (By Series, Industry & Bay Type, ACE850FO Fiber Digital Retrofit)

Voltage range: 3kV～35kV medium-voltage distribution network, industrial and municipal user substations, excluding 110kV/220kV transmission grid. All series EOL, widely deployed in legacy retrofit projects; new projects use Easergy P3/P5 as replacement.

Sepam 40 Series｜Economical, basic distribution protection

Positioning: Basic protection, limited I/O, simple logic. For bays with simple protection requirements and budget constraints.

Typical Bay Applications

1. General feeder outgoing (S40/S41): Plant / park simple outgoing protection, overcurrent and residual earth fault
2. PT voltage cabinet (S50): Busbar voltage monitoring, overvoltage/undervoltage, frequency supervision
3. Small distribution transformer (T40): 10kV/0.4kV distribution transformer protection, simple instantaneous overcurrent, overload and earth fault
4. Busbar tie / dual-source basic ATS (S42/T42): Simple automatic transfer for single busbar sectionalized scheme with basic logic
5. Medium & small MV motors (M41): Ordinary fans and pump motor protection
6. Small diesel generator (G40): Standalone emergency generator protection

Target Industries

Commercial complexes, hospitals, small manufacturing plants, distribution kiosks, simple wastewater treatment plants

Normally deployed with RS485 Modbus; ACE850FO is added for IEC61850/GOOSE fiber networking.

Sepam 60 Series｜Enhanced, complex distribution, medium logic requirements

Positioning: More I/O points, stronger interlock logic, multi-condition interlock supported, better recording performance than Sepam40.

Typical Bay Applications

1. Feeder & incoming protection (S60/S62): Directional protection, busbar ATS, dual-source interlock, main incoming cabinets in industrial plants
2. Medium-voltage motors (M61): Heavy-duty pumps, crushers, compressors with RTD temperature monitoring
3. Distribution transformers (T60/T62): Distribution transformers with temperature interlock and trip blocking
4. Capacitor banks (C60): Reactive power compensation capacitor protection, unbalance and overvoltage protection
5. Paralleling small generators (G60/G62): Protection for multiple small generators in parallel operation

Target Industries

Pharmaceutical plants, paper mills, medium-sized waterworks, 10kV substations for data centers, rail auxiliary substations

ACE850FO is commonly used in digital retrofit to build fiber ring networks for fast GOOSE interlock.

Sepam 80 Series｜High-end programmable, Logipam, complex primary equipment protection (Most common ACE850FO pairing)

Positioning: Top product line. Supports custom Logipam programming, high sampling fault recording, bus differential, full generator protection. Preferred for digital substation retrofit.

Typical Bay Applications

1. Incoming / critical feeder (S80/S81/S82/S84): Directional residual, islanding detection, breaker failure, complex ATS logic
2. Power transformers (T81/T82/T87): Main distribution transformers, interfacing Buchholz, oil temperature, pressure relief non-electrical signals
3. High-power MV motors (M81/M87/M88): Steel & mining heavy-duty motors, bearing temperature monitoring, stall and rotor protection
4. Generators (G82/G87/G88): Diesel & biogas generators, loss of excitation, reverse power, overexcitation, underfrequency, multi-unit paralleling
5. Busbar protection (B80/B83): Busbar differential protection for fast fault clearing on sectionalized single busbar
6. Large capacitor banks (C86): Multi-section capacitor banks with segmented unbalance protection

Target Industries

Petrochemical, coal chemical, metallurgy & steel, mining, large data centers, power plant auxiliary power, airports, ports, large pumping stations. Widely used in legacy digital retrofit projects (fiber ring + IEC61850 GOOSE interlock) with ACE850FO.

Cross-Series Industry Summary

Industry: Petrochemical, metallurgy & steel, mining, paper, pharmaceutical, cement, heavy manufacturing auxiliary power

Infrastructure: Airports, ports, rail transit, tunnels, municipal water & wastewater plants

Building power distribution: Large commercial complexes, tertiary hospitals, 10kV user substations for data centers

Energy: On-site power plants, diesel generator stations, distributed energy grid-connection bays

Quick Selection Guide

1. Basic overcurrent & earth fault only, no complex interlock → Sepam40
2. ATS, motor temperature monitoring, capacitor protection, medium complexity interlock → Sepam60
3. Bus differential, transformer non-electrical protection, high-power motor, generator paralleling, custom logic, IEC61850/GOOSE fiber ring → Sepam80 + ACE850FO

Engineering Notes

1. Core value of ACE850FO: GOOSE cross-cabinet interlock for Sepam80 ring deployment, replacing hardwired secondary wiring with superior EMI performance in switchgear environments
2. Limitation: IEDs are EOL discontinued. Not allowed for new projects; only for legacy substation retrofit and spare replacement
3. Communication: Native Modbus RTU on IED; IEC61850, GOOSE and RSTP fiber ring require external ACE850FO / ACE850TP

Sepam 60 Series Full Model List (Schneider EOL Protection IEDs, compatible with ACE850FO fiber module)

Prefix definition:

S = Feeder / incoming protection

T = Transformer protection

M = Motor protection

G = Generator protection

C = Capacitor protection

Sepam60 shares unified hardware platform; protection functions are implemented by embedded firmware. Native RS485 Modbus RTU; IEC61850, GOOSE and fiber ring require ACE850FO (59659) or ACE850TP copper module.

Model Details & Core Functions

1. S60｜Feeder / Incoming Protection

General incoming and feeder cabinets, phase overcurrent, residual earth fault, voltage & frequency monitoring, basic logic interlock; suitable for plant outgoing and single busbar incoming bays.

2. S62｜Directional Incoming / Busbar, Automatic Transfer

Directional overcurrent and directional residual earth fault protection. Supports busbar ATS, dual-source interlock and loop incoming discrimination. Widely used for single busbar sectionalized incoming and bus tie cabinets; the most popular model in Sepam60.

3. T60｜Distribution Transformer Protection

10kV distribution transformer protection, instantaneous overcurrent, overload, residual current and oil temperature monitoring for conventional plant distribution transformers.

4. T62｜Transformer + Incoming Interlock / ATS

Transformer protection plus source automatic transfer logic. Able to interface transformer non-electrical signals (temperature, pressure). Designed for critical distribution transformers.

5. M61｜Medium-Voltage Motor Protection

Medium-voltage heavy-duty motors (pumps, fans, crushers). Stall, overload, unbalance and earth fault protection. Supports up to 16 RTD inputs for stator / bearing temperature measurement. The only motor model in Sepam60.

6. G60｜Standalone Generator Protection

Protection for standalone diesel generators. Overcurrent, overvoltage/undervoltage, underfrequency and overload for independent emergency generator sets.

7. G62｜Generator Paralleling Protection

Generator grid paralleling protection with reverse power, out-of-step and synchronisation-related logic for multi-generator parallel operation.

8. C60｜Capacitor Bank Protection

Medium-voltage reactive compensation capacitor cabinet protection, overcurrent, overvoltage, residual and unbalance protection for single-section capacitor banks.

Common Hardware Specifications of Sepam60

Analog inputs: 4 current inputs, 3 voltage inputs

Digital I/O: 28 DI, 16 DO

Temperature measurement: Max. 16 RTD channels

Logic: Built-in logic equation editor (Note: Sepam60 does not support full Logipam ladder programming available on Sepam80)

Fault recording: 12 samples per cycle

HMI: 3 optional panels (basic / standard / large display)

Commissioning software: SFT2841

Engineering Selection Tips

1. EOL status: Sepam60 IED discontinued. New projects recommended Easergy P3. ACE850FO can be fitted for GOOSE fiber networking in legacy retrofit.
2. Compare with Sepam40: Higher I/O capacity, more RTD channels and stronger custom logic.
3. Compare with Sepam80: No advanced Logipam programming, no bus differential and no high sampling oscillography.